TULARE, Calif. (AP) — Newt Gingrich's presidential campaign has a history of near-death experiences and he insists another resurrection is on its way.

"I'm very happy to continue this campaign based on real solutions that ... are going to attract a lot of Americans," Gingrich said Monday during a fundraising swing in California. "We've done it twice and I suspect you're about to see us do it again."

The third time may not be the charm. Gingrich sustained a string of disappointing performances in several state contests last week and has watched rival Rick Santorum emerge as the leading conservative opponent to Mitt Romney.

While Romney and Santorum move toward a face-off in Michigan's primary Feb. 28 and Romney campaigns to win Arizona the same day, Gingrich has all but stepped off the trail to focus on raising money. Ahead lie the 10-state Super Tuesday contests of March 6, including a handful of Southern states where he hopes he can revive his sputtering candidacy.

"Newt has to do two things simultaneously: Drive a movement for the 60 to 75 percent of Republicans who are conservative and don't want Romney to get the nomination," said Rick Tyler, a former Gingrich aide now with Winning Our Future, a "super" political action committee backing his candidacy. "Then he has to get out the primary map and look at states that are conservative and focus on them."

Gingrich has a record of resuscitating his candidacy when others have written him off.

He surged into a lead in Iowa not long before that state's first-in-the-nation caucuses and just months after his entire team of advisers quit over disagreements about campaign strategy. That rise was halted after the pro-Romney super PAC Restore Our Future deployed $3 million in ads casting Gingrich as a baggage-laden Washington hypocrite.

His campaign was revived again in South Carolina, where he trounced Romney despite a similar barrage of negative super PAC ads. Then his momentum was halted in Florida's primary Jan. 31, where Restore Our Future and the Romney campaign together spent $15 million on attack ads.

Since then, Gingrich has struggled.

He came in a distant second to Romney in Nevada on Feb. 4 and badly lost four straight contests last week. Santorum won in Minnesota, Missouri and Colorado, breathing new life into his own limping candidacy.

Gingrich also placed a disappointing third in the Conservative Political Action Conference straw poll last weekend despite giving a speech that drew praise and cheers from attendees.

If it's a disheartening turn of events for Gingrich, you'd never hear him say it.

He's brought his signature bravado to a handful of public appearances in California — from a sparsely attended event at a Mexican restaurant outside Los Angeles to a tea party gathering in Pasadena to a stroll through a huge agriculture expo in Tulare, where he admired farm equipment. He delights in excoriating bureaucrats, chiding President Barack Obama as a "radical" and casting himself as the only GOP contender with bold ideas for fixing the nation's problems.

"You need somebody who understands what America needs to do to be successful, someone who's had the experience of doing it, and then you've got to have somebody who can go out and explain it to the American people. That's why I'm running," he told reporters in Tulare.

For all the big ideas, Gingrich's campaign still has something of an improvisational feel. He ventured to the San Diego Zoo on Tuesday without bringing or notifying the national reporters assigned to cover him. He visited the elephant exhibit and fed a panda, with only a handful of local press — alerted by the zoo, not his campaign — on hand to record the visit.

Gingrich says he's retooled his pitch to be more positive and solutions-oriented, a move away from his sometimes-caustic attacks on Romney's record at the investment firm Bain Capital. But he relished a chance to knock Santorum, who suggested last week that women should not serve in military combat.

"I just think Rick completely misunderstands the nature of modern warfare," Gingrich said. "The fact is if you are serving in uniform in Iraq or Afghanistan ... you're in combat, whatever your technical assignment."

Gingrich's wife, Callista, has begun speaking publicly on his behalf after months of standing silently at his side. Her willingness to step out reflects an effort to improve his standing with female voters, who polls show have been particularly skeptical of his candidacy. One reason may be Gingrich's marital history, including two divorces and acknowledged infidelities.

Gingrich's supporters dismiss Santorum's rise as rookie luck, suggesting the former Pennsylvania senator has simply been the beneficiary of the air war that's been trained on Gingrich.

"Santorum is not the recipient of 13,000 false advertisements in Iowa, Florida and South Carolina," Tyler said, writing off Santorum's recent victories as "meaningless" because the states he won will not award delegates until the spring.

Gingrich and his advisers have mapped out a strategy focusing on Super Tuesday states including Georgia, Oklahoma, Ohio and Tennessee; Alabama and Mississippi, which hold primaries March 13; and Texas, where the primary is April 3. That state's governor, Rick Perry, endorsed Gingrich after dropping out of the Republican presidential contest last month.

Campaign officials insist fundraising is going well enough for Gingrich to be competitive in a number of states. But he hasn't run any television advertising since the Florida primary at the end of January, nor has the Winning Our Future super PAC. The group's major patron, casino magnate Sheldon Adelson's family, has contributed $11 million to the super PAC but hasn't announced plans for further financial help.

With so many competitive primaries and caucuses looming and attention focused on the contest between Romney and Santorum, some supporters are asking whether Gingrich's luck may have finally run out. He vehemently pushes back on that suggestion.

"I'm still here," he told tea party supporters, to loud applause.

Bob Walker, a former Pennsylvania congressman and a top adviser to Gingrich, pleaded for patience.

"People who are out there calling for him to get out don't seem to understand his whole political career," Walker said. "We always knew it would be a long campaign. This is just one more example of the campaign taking its course."